1. Field of the Invention
The present invention relates to a substrate processing apparatus and a substrate processing method for performing coating processing of a resist solution or developing processing, for example, for a substrate such as a semiconductor wafer, a glass substrate for a liquid crystal display, or the like.
2. Description of the Related Art
In a photolithography process in the process of fabricating a semiconductor device, for example, resist coating processing of forming a resist film on the surface of a wafer, exposure processing of exposing the wafer by irradiating a pattern on the wafer, developing processing of developing the exposed wafer, heating processing and cooling processing before the coating processing, before and after the exposure processing, and after the developing processing, and the like are performed. Such processing is performed in processing units provided individually, and these processing units are unified to compose a coating and developing processing system so as to continuously perform such successive processing.
Generally, the coating and developing processing system is composed of a loader/unloader section for carrying a wafer into/out of the coating and developing processing system, a processing section having a coating processing unit, a developing processing unit, a thermal processing unit, and the like and performing the majority of the aforesaid wafer processing, an aligner outside the system for subjecting the wafer to exposure processing, and an interface section, provided adjacent to the processing section and the aligner, for delivering the wafer between the processing section and the aligner.
When the wafer is processed in this coating and developing processing system, in order to prevent impurities such as fine particles from adhering to the wafer, air cleaned by an air purifier or the like is supplied as down-flowing air into the coating and developing processing system, while an atmosphere inside the coating and developing system is exhausted, whereby the wafer can be processed in a clean condition.
Moreover, to realize sensitive exposure, a chemically amplified resist is used. The chemically amplified resist has a basic polymer insoluble in an alkaline developing solution, for example, and an acid generator, and obtains high resolution by causing polarity changes in an exposed portion and an unexposed portion by the use of a catalytic reaction of an acid. In the aligner, a circuit pattern is exposed in a resist film by using a mask, and an elimination reaction is caused to a protective group which protects a hydroxyl group of the basic polymer by the acid produced at this time. Thereafter, the wafer is transferred to the thermal processing unit, where the catalytic reaction of the acid is accelerated to quicken the elimination reaction by PEB (post-exposure baking) which is heating after exposure, and thereby the exposed portion, for example, is made soluble in the alkaline developing solution. The wafer is then transferred to the developing processing unit and the portion which is made soluble is removed by the developing solution, whereby a precise circuit patter is obtained.
In recent years, however, exposure technology in which a beam with a shorter wavelength is used is being developed to form a finer and more precise circuit pattern, and when the beam with the shorter wavelength is used, it is confirmed that impurities at molecular level such as oxygen, basic substances, ozone, and vapor which have been insignificant so far exert a bad influence on the formation of the precise circuit pattern. Specially when the impurities adhere to the wafer on the occasion of exposure, an appropriate pattern is not exposed, and thus a drop in yield can not be avoided.
Accordingly, it is necessary for the impurities not to adhere to the wafer under processing, but the use of clean air as before is inappropriate because the air itself contains impurities such as oxygen.
An acid produced at the time of exposure has high reactivity, and hence shows a neutralization reaction with basic substances in air during the transfer of the wafer. In this case, the acid is deactivated, which causes a change in the formation of a slightly soluble surface layer and the line width of the circuit pattern. The elimination reaction of a protective group depends on the temperature, and some kind of chemically amplified resist causes the elimination reaction of the productive base by a catalytic reaction of the acid, for example, even in the state of an ordinary temperature. Therefore, there is the possibility that the elimination reaction progresses during transfer before PEB, which causes pattern deformation, the deterioration of reproducibility, and the like.
Even in such pattern deformation as can be conventionally ignored, there is still room for improvement in these days when a more precise circuit pattern is demanded, but such clean air and system configuration as before can not meet the demand.
Moreover, the wafer comes and goes between the processing section and the exposure processing section via the interface section. There is the possibility that the neutralization reaction of the acid or the elimination reaction of the productive base occur after exposure as described above, while the acid is not produced before exposure, and consequently the conditions of an atmosphere inside the interface section demanded before and after exposure are different. Thus, the formation of the optimum atmosphere for the condition of the wafer after exposure in the interface section is demanded.
An object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of preventing fine impurities at molecular level from adhering to a substrate such as a wafer or the like.
Another object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of preventing fine impurities at molecular level from adhering to a substrate such as a wafer or the like and individually controlling atmospheres in substrate routes before and after exposure in an interface section to prevent acid deactivation, pattern deformation, and the like.
Still another object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of improving the uniformity of developing line width in a surface of a substrate and between substrates by transferring the exposed substrate to a heating section while inhibiting the progress of a resolution reaction of a resist and performing heating processing there.
To attain the aforesaid objects, according to the present invention, a coating and developing processing system, which is a system for performing coating and developing processing for a substrate and characterized by comprising a loader/unloader section for carrying the substrate into/out of the system; a processing section having a coating processing unit for at least forming a coating film on the substrate, a developing processing unit for developing the substrate, a thermal processing unit for thermally processing the substrate, and a first transfer device for carrying the substrate into/out of the coating processing unit, the developing processing unit, and the thermal processing unit; an interface section having a second transfer device for transferring the substrate at least via a route between the processing section and an aligner for subjecting the substrate to exposure processing; a gas supply device for supplying an inert gas to the interface section; and an exhaust means for exhausting an atmosphere in the interface section in a casing of this system, is provided. Incidentally, the thermal processing unit includes a heating processing unit, a cooling processing unit, and a heating/cooling processing unit, and the like. Further, the processing section may include other processing units such as an extension unit for making the substrate wait and an adhesion unit for supplying a predetermined processing solution onto the substrate in order to enhance adhesion properties of the substrate and a coating solution.
The aforesaid supply of the inert gas to the interface section by the gas supply device and exhaust of the atmosphere in the interface section by the exhaust means enable the removal of impurities such as oxygen and vapor from within the interface section and the maintenance of the atmosphere inside the interface section in a clean condition. Consequently, the adhesion of impurities to the substrate is suppressed, whereby the substrate is processed suitably. Especially, if impurities adhere to the substrate when the substrate undergoes exposure processing, the impurities absorb energy of a laser beam and so on used in exposure, and as a result, the exposure processing is not performed suitably. Accordingly, it is important to maintain the interface section, which the substrate passes through immediately before the exposure processing, in a clean condition. It should be mentioned that the aforesaid inert gas is an inert gas for a processing solution used in the coating and developing processing system, for example, a coating solution such as a resist solution, and a developing solution, and a gas not containing oxygen, moisture, and organic substances, for example, nitrogen gas, argon, neon, or the like.
In the present invention, the system may comprise: a gas supply device for supplying the inert gas to an area having at least the thermal processing unit and the first transfer device in the processing section; and an exhaust means for exhausting an atmosphere at least in the area.
The aforesaid supply of the inert gas into the processing section in addition to the interface section enables the removal of impurities such as oxygen from within the processing section and the maintenance of the atmosphere inside the processing section in a clean condition, resulting in suppression of adhesion of the impurities to the substrate. Especially after a coating film is formed on the substrate and the substrate is subjected to heating processing, impurities are apt to adhere to the surface of the substrate. If impurities adhere in this case, exposure processing to be performed immediately after this can not be performed suitably. Hence, the removal of impurities from the surface of the substrate in the processing section is important. Incidentally, although the inert gas may be supplied at least into the aforesaid area in the processing section, it also may be supplied into an area other than the aforesaid area in the processing section, that is, an area where the coating processing unit and the developing processing unit are placed.
Further, in the present invention, the system may comprise: a gas supply device for supplying the inert gas to the loader/unloader section; and an exhaust means for exhausting an atmosphere in the loader/unloader section.
As described above, also in the loader/unloader section, the substrate can be more perfectly protected from impurities such as oxygen by supplying the inert gas thereto and maintaining the loader/unloader section in a clean condition as in the interface section and the area in the processing section.
The coating and developing processing system described so far may comprise a partition plate shutting off the atmosphere in the interface section from the atmosphere in the processing section, the partition plate may have a transit opening for delivering the substrate between the area in the processing section and the interface section, and the transit opening may have a shutter allowing the transit opening to freely open and close.
By dividing the interface section and the processing section by the partition plate as described above, the flow of the atmosphere inside the processing section into the interface section which is maintained in a clean condition thanks to the aforesaid supply of the inert gas can be suppressed. Moreover, by providing the transit opening in the partition plate and freely opening and closing the transit port by the shutter, the shutter can be opened only when the substrate is delivered between the interface section and the area in the processing section, which can prevent the mutual interference of the atmospheres in the processing section and the interface section and keep the atmosphere in the interface section clean. The reason why the position of the transit opening is limited to the partition plate in the area in the processing section is that the substrate is never transferred directly from any area other than the area in the processing section, that is, an area having the coating processing unit and the developing processing unit to the interface section.
Furthermore, in the present invention, the system may comprise another partition plate shutting off the atmosphere in the processing section from the atmosphere in the loader/unloader section, the aforesaid another partition plate may have another transit opening for delivering the substrate between the area in the processing section and the loader/unloader section, and the aforesaid another transit opening may have another shutter allowing the aforesaid another transit opening to freely open and close.
The aforesaid provision of the partition plate also between the processing section and the loader/unloader section and provision of the transit opening and the shutter for delivering the substrate between the area in the processing section and the loader/unloader section in the partition plate make it possible to suppress the interference of the atmospheres in the processing section and the loader/unloader section and maintain a predetermined atmosphere in the processing section. Especially, when the inert gas is supplied to the processing section as in claim 2, the flow of the relatively unclean atmosphere inside the loader/unloader section into the processing section is prevented, whereby the atmosphere in the processing section is maintained in a clean condition, and thus the adhesion of impurities to the substrate is suppressed.
In the coating and developing processing system described so far, it is suitable to clean at least a part of the atmosphere exhausted by the exhaust means and send the same as the inert gas to the gas supply device again. The aforesaid reuse of the atmosphere exhausted by the exhaust means in the gas supply device as the inert gas can reduce the amount of the inert gas newly required, leading to a reduction in the amount of the inert gas.
In the present invention, the system may comprise a temperature regulating means for regulating a temperature of the inert gas. This provision of the temperature regulating means makes it possible to maintain the atmosphere in the coating and developing processing system to which the inert gas is supplied at a predetermined temperature, whereby the processing, transfer, and the like of the substrate can be performed in the atmosphere at the predetermined temperature.
Moreover, in the present invention, it is more preferable that the pressure inside the interface section be set lower than the pressure inside the aligner.
The aforesaid setting of the pressure inside the interface section lower than the pressure inside the aligner can prevent the atmosphere in the interface section from flowing into the aligner. Hence, exposure processing for the substrate in the aligner is performed suitably in a predetermined atmosphere.
In the present invention, the pressure inside the interface section may be set lower than the pressure inside the area in the processing section. The aforesaid setting of the pressure inside the interface section lower than the pressure inside the area in the processing section can prevent the atmosphere in the interface section from flowing into the area in the processing section. Hence, a predetermined atmosphere is maintained in the processing section in which substrate processing units are provided and a variety of substrate processing is performed, and the variety of substrate processing can be performed suitably.
Further, in the present invention, the pressure inside the area in the processing section may be set higher than the pressure inside the loader/unloader section. The aforesaid setting of the pressure inside the area in the processing section higher than the pressure inside the loader/unloader section can prevent the flow of the atmosphere inside the loader/unloader section into the area in the processing section. Hence, similarly to the above, a predetermined atmosphere is maintained in the area in the processing section, and thus the variety of substrate processing can be performed suitably.
Furthermore, in the present invention, the pressure inside the area in the processing section may be set lower than the pressures inside the coating processing unit and the developing processing unit in the processing section. The aforesaid setting of the pressure inside the area in the processing section lower than the pressures inside the coating processing unit and the developing processing unit can prevent atmospheres in the coating processing unit and the developing processing unit from flowing into the area. Accordingly, the coating processing unit or the like in which the atmosphere is controlled more severely than the processing units such as a predetermined atmosphere is maintained in the thermal processing unit in the area, and thus coating processing and developing processing which are most important in this coating and developing processing can be performed suitably.
In the coating and developing processing system described thus far, the pressure inside the casing is set higher than the pressure outside the coating and developing processing system. By setting the pressure inside the casing higher than the pressure outside the coating and developing processing system as described above, the flow of an atmosphere outside the coating and developing processing system into the casing is prevented. Therefore, the contamination of an atmosphere inside the casing where the substrate is processed by the relatively dirty atmosphere outside the coating and developing processing system can be suppressed. It should be noted that the pressure outside the coating and developing processing system means the pressure inside a room where the coating and developing processing system is installed, for example, the pressure inside a clean room.
The present invention according to another aspect provides a coating and developing system, which is a system for performing coating and developing processing provided with: a processing section having a coating processing unit for at least forming a coating film on a substrate, a developing processing unit for developing the substrate, a thermal processing unit for thermally processing the substrate, and a substrate transfer device for carrying the substrate into/out of the coating processing unit, the developing processing unit, and the thermal processing unit; and an interface section for transferring the substrate via a route between the processing section and an aligner for subjecting the substrate to exposure processing, inside the casing, and characterized in that a first thermal processing unit for thermally processing the substrate before exposure, a first transfer device for transferring the substrate before exposure, a second thermal processing unit for thermally processing the substrate after exposure, and a second transfer device for transferring the substrate after exposure are arranged in the interface section, and that a first gas supply device for supplying an inert gas to an area before exposure having the first thermal processing unit and the first transfer device in the interface section, a first exhaust means for exhausting an atmosphere in the area before exposure, a second gas supply device for supplying the inert gas to an area after exposure having the second thermal processing unit and the second transfer device in the interface section, and a second exhaust means for exhausting an atmosphere in the area after exposure are provided. Incidentally, the thermal processing unit, the first thermal processing unit, and the second thermal processing unit include a heating processing unit, a cooling processing unit, a heating/cooling processing unit, and the like. Further, the processing section may include other processing units such as an extension unit for making the substrate wait and an adhesion unit for supplying a predetermined processing solution onto the substrate in order to enhance adhesion properties of the substrate and a coating solution.
According to the present invention, in the interface section, by supplying the inert gas to the area before exposure by the first gas supply device and exhausting the atmosphere in this area before exposure by the first exhaust means, impurities such as oxygen and vapor can be removed from within the area before exposure, and the area before exposure can be maintained in a clean condition. Consequently, the substrate can be transferred in a clean atmosphere from heating processing immediately before exposure processing to exposure processing, whereby the adhesion of impurities can be prevented. Especially, after the substrate on which a coating film is formed is subjected to heating processing, impurities are apt to adhere to the surface of the substrate. Moreover, if impurities adhere to the substrate when the substrate undergoes exposure processing, the impurities absorb energy of a laser beam and so on used in exposure, and as a result, there is the possibility that the exposure processing is not performed suitably. But, by maintaining the area before exposure in the interface section, which the substrate passes through immediately before the exposure processing, in a clean condition, the substrate can be processed suitably. It should be mentioned that the aforesaid inert gas is an inert gas for a processing solution used in the coating and developing processing system, for example, a coating solution and a developing solution, and a gas not containing oxygen, moisture, and organic substances, for example, nitrogen gas, argon, neon, or the like.
Moreover, by supplying the inert gas to the area after exposure by the second gas supply device and exhausting the atmosphere in this area after exposure by the second exhaust means, the area after exposure can be maintained in a clean condition similarly to the area before exposure. Especially when a chemically amplified resist which forms a circuit pattern on the substrate by a catalytic reaction of an acid is used, the acid is deactivated if impurities adheres to the substrate after exposure processing. But, the aforesaid maintenance of the area after exposure in the interface section, which the substrate passes through immediately after the exposure processing, in a clean condition can prevent the acid deactivation, leading to suitable performance of the subsequent developing processing.
The inert gas is supplied to each of the areas by the individual gas supply device, whereby atmospheres peculiar to the respective areas can be maintained in the areas before exposure and after exposure.
Since the peculiar atmospheres can be maintained in the respective areas, the second gas supply device may supply the inert gas having a temperature lower than the temperature of the inert gas to be supplied by the first gas supply device, or may supply the inert gas having a low oxygen concentration as described in claim 15.
When the first gas supply device supplies, for example, the inert gas having an ordinary temperature to the area before exposure, the second gas supply device supplies the inert gas having a temperature lower than the ordinary temperature, whereby the atmosphere in the area after exposure can be maintained in a low-temperature condition. Especially when the aforesaid chemically amplified resist has a property such that a protective group which protects a hydroxyl group of a basic polymer even at the ordinary temperature shows an elimination reaction, the elimination reaction of the protective group progresses on the substrate during its transfer within the area after exposure if the temperature of the atmosphere in the area after exposure is higher than the ordinary temperature. The maintenance of the area after exposure in a low-temperature condition, however, can inhibit the elimination reaction of the protective group during transfer. Hence, a circuit pattern can be satisfactorily formed. Moreover, the supply of the inert gas having a low oxygen concentration by the second gas supply device makes it possible to keep the concentration of oxygen in the atmosphere in the area after exposure low, which can prevent acid deactivation.
In the present invention, a partition plate shutting off the atmosphere in the area before exposure from the atmosphere in the area after exposure can be provided.
According to the present invention, the partition plate shuts off the area before exposure from the area after exposure in the interface section, which can prevent the mutual interference of the atmospheres, resulting in the maintenance of atmospheres peculiar to the respective areas in the areas before and after exposure. Specially when the area after exposure is maintained at the low temperature, it is effective to provide a partition plate between the areas as described above.
In the present invention, the system may have another partition plate shutting off an atmosphere in the processing section from an atmosphere in the interface section, the aforesaid another partition plate may have a first transit opening for delivering the substrate between the processing section and the area before exposure and a second transit opening for delivering the substrate between the processing section and the area after exposure, the first transit opening may have a first shutter allowing the first transit opening to freely open and close, and the second transit opening may have a second shutter allowing the second transit opening to freely open and close.
According to the present invention, by dividing the processing section and the interface section by another partition plate, the flow of the atmosphere inside the processing section into the areas before and after exposure in the interface section maintained in a clean condition by the aforesaid supply of the inert gas can be prevented. Further, the provision of the first shutter which can freely open and close at the first transit opening, for example, makes it possible to open the first shutter and let the substrate pass only when the substrate is delivered from the processing section to the area before exposure. Furthermore, the provision of the second shutter which can freely open and close at the second transit opening makes it possible to open the second shutter and let the substrate pass only when the substrate is delivered from the area after exposure to the processing section. Accordingly, the mutual interference of the atmospheres in the processing section and the interface section can be prevented, and the areas before and after exposure in the interface section can be maintained clean.
In the present invention, the temperature of the inert gas may be regulated. This regulation of the inert gas at a predetermined temperature allows atmospheres in respective areas to which the inert gas is supplied to be maintained at the predetermined temperature.
In the present invention, it is desirable to set the pressure in the interface section lower than the pressure in the aligner. According to such a structure, the flow of the atmospheres in the areas before and after exposure in the interface section into the aligner in which the atmosphere is severely controlled can be prevented by setting the pressure in the interface section lower than the pressure in the aligner.
A substrate processing apparatus of the present invention according to still another aspect comprises: a processing section for performing coating and developing processing for a substrate; an interface section for transferring the substrate at least via a route between the processing section and an aligner for subjecting the substrate to exposure processing; a chamber, disposed inside the interface section, for temporarily holding the substrate delivered from the processing section and to be transferred to the aligner; and an atmosphere controller for controlling an atmosphere in the chamber.
In the present invention, since the substrate delivered from the processing section and to be transferred to the aligner is temporarily held in the chamber in which the atmosphere is controlled, for example, the variation with time of the resist before exposure can be suppressed, and a change in the property of the resist can be prevented. As a result, the uniformity of line width can be raised.
The atmosphere controller here reduces the pressure inside the chamber and supplies an inert gas or dry air into the chamber.
The chamber can be structured to comprise: a purge room for temporarily holding and purging the substrate introduced into the chamber; a buffer room for holding the substrate; and a transfer device for transferring the substrate between the purge room and the buffer room. Incidentally, it is desirable that the buffer room have a transit opening for directly carrying out the substrate to the aligner.
A substrate processing apparatus of the present invention according to another aspect comprises: a coating processing unit for at least forming a coating film on a substrate; a developing processing unit for developing the substrate; a thermal processing unit for thermally processing the substrate; a transfer device for carrying the substrate into/out of the coating processing unit, the developing processing unit, and the thermal processing unit; and a blower for sending an inert gas to the substrate which is being transferred by the transfer device.
In the present invention, the blower for sending the inert gas to the substrate which is being transferred by the transfer device is provided, which eliminates influence on pattern resolution, for example, due to the occurrence of hydrolysis of the resist caused by moisture in atmospheric air during the transfer of the substrate after resist-coating and the bonding of the resist with oxygen in the atmospheric air.
Specifically, for example, the transfer device has tweezers for holding the substrate, and the blower has a top cover having a blast port for sending the inert gas from above the tweezers. In this case, a plurality of the blast ports may be provided to correspond to the shape of the tweezers, or may be provided to correspond to the shape of the substrate. The blower may be structured to have a temperature control mechanism for controlling the temperature of the inert gas or a humidity control mechanism for controlling the humidity of the inert gas. Incidentally, it is most efficient that the blower sends the inert gas when the transfer device transfers the substrate from the coating processing unit to the thermal processing unit.
A substrate processing apparatus of the present invention according to still another aspect is characterized by comprising: a reaction inhibiting section for performing processing of inhibiting the progress of a resolution reaction of a resist for a substrate coated with the resist and exposed; a heating section for heating the substrate processed in the reaction inhibiting section to progress the resolution reaction of the resist; a cooling section for cooling the substrate heated in the heating section to inhibit the progress of the resolution reaction of the resist; and a developing processing section for performing coating processing of a developing solution for the substrate cooled in the cooling section.
Specifically, the apparatus comprises: a cassette station including a mounting section on which a substrate cassette housing a plurality of substrates is mounted and a delivery means for receiving and sending the substrate from/to the substrate cassette mounted on the mounting section; a processing station, connected to the cassette station, for processing the substrate transferred by the delivery means; an aligner provided on the opposite side to the cassette station of the processing station; and an interface station, connected to the opposite side to the cassette station of the processing station, for delivering the substrate between the processing station and the aligner, and the interface station includes a reaction inhibiting section for performing processing of inhibiting the progress of a resolution reaction of a resist for a substrate coated with the resist and exposed, and the processing station includes a heating section for heating the substrate processed in the reaction inhibiting section to progress the resolution reaction of the resist, a cooling section for cooling the substrate heated in the heating section to inhibit the progress of the resolution reaction of the resist, and a developing processing section for performing coating processing of a developing solution for the substrate.
In such a substrate processing apparatus, the progress of the resolution reaction of the resist is inhibited during the transfer of the substrate from the aligner to the heating section, and thus in the heating section, the resolution reaction progresses on the same condition for the substrate in which the extent of the progress of the resolution reaction is made uniform. Therefore, when developing processing is performed, the extent of the progress of the resolution reaction is made uniform over the entire substrate, whereby the occurrence of the ununiformity of developing line width is suppressed.
In the above, it is desirable to place the reaction inhibiting section near the aligner, in which case the time of transfer between the aligner and the reaction inhibiting section is shortened, whereby the extent of the progress of the resolution reaction of the substrate transferred to the reaction inhibiting section is made more uniform, resulting in a rise in the uniformity of developing line width.
In this case, it is desirable that the reaction inhibiting section have a structure characterized by inhibiting the progress of the resolution reaction of the resist by cooling the substrate coated with the resist and exposed so as not to cause dew formation. Also, it is desirable that it have a structure characterized by inhibiting the progress of the resolution reaction of the resist by making the amount of moisture adhering to the substrate coated with the resist and exposed smaller than the amount of moisture adhering to the substrate when the substrate is transferred to the reaction inhibiting section, and characterized, for example, by making the amount of the moisture adhering to the substrate smaller than the amount of the moisture adhering to the substrate when the substrate is transferred to the reaction inhibiting section by supplying a gas having a humidity lower than the humidity of air in an atmosphere in which the reaction inhibiting section is placed.
The resist is a chemically amplified resist, the resolution reaction of which is progressed by an acid produced by exposure, for example, in which case the resolution reaction of the resist is a reaction that an acid produced by exposure decomposes a basic resin which is a main component of a resist material or changes its molecular structure to make the basic resin soluble in a developing solution.
Therefore, in a substrate processing method of the present invention comprising the steps of: heating a substrate coated with a resist and exposed in a heating section to progress a resolution reaction of the resist; cooling the substrate to inhibit the progress of the resolution reaction of the resist; and performing coating processing of a developing solution for the substrate, the exposed substrate is transferred to the heating section with the resolution reaction of the resist being inhibited.
Such a method is carried out by a substrate processing apparatus characterized by comprising: an exposure section for exposing a substrate coated with a resist; a heating section for heating the exposed substrate to progress a resolution reaction of the resist; a cooling section for cooling the heated substrate to inhibit the progress of the resolution reaction of the resist; and a developing processing section for performing coating processing of a developing solution for the cooled substrate, and transferring the exposed substrate to the heating section by a substrate transfer means with the resolution reaction of the resist being inhibited.
In this case, for example, the exposed substrate is transferred to the heating section with the progress of the resolution reaction of the resist being inhibited by being cooled so as not to cause dew formation. Moreover, the substrate may be transferred to the heating section with the progress of the resolution reaction of the resist being inhibited by making the amount of moisture adhering to the substrate when the substrate is transferred to the heating section smaller than the amount of moisture adhering to the substrate after exposure, in which case the exposed substrate is transferred to the heating section while a gas having a humidity lower than air is being supplied to the substrate.
Specifically, the apparatus has a structure characterized by comprising: a cassette station including a mounting section on which a substrate cassette housing a plurality of substrates is mounted and a delivery means for receiving and sending the substrate from/to the substrate cassette mounted on the mounting section; a processing station, connected to the cassette station, for processing the substrate transferred by the delivery means; an aligner provided on the opposite side to the cassette station of the processing station; an interface station, connected to the opposite side to the cassette station of the processing station, for delivering the substrate between the processing station and the aligner, and characterized in that the interface station comprises a heating section for heating the exposed substrate to progress a resolution reaction of a resist, the processing station comprises: a cooling section for cooling the substrate heated in the heating section to inhibit the progress of the resolution reaction of the resist; and a developing processing section for performing coating processing of a developing solution for the substrate, and that the interface station is cooled so as not to cause dew formation on the substrate to inhibit the progress of the resolution reaction of the resist.
In such a invention, the progress of the resolution reaction of the resist is inhibited during the transfer of the substrate from the aligner to the heating section, and thus in the heating section, the resolution reaction progresses on the same condition for the substrate in which the extent of the progress of the resolution reaction is made uniform. Therefore, when developing processing is performed, the extent of the progress of the resolution reaction is made uniform over the entire substrate, whereby the occurrence of the ununiformity of the developing line width is suppressed.
Moreover, the resist is a chemically amplified resist, the resolution reaction of which is progressed by an acid produced by exposure, for example, in which case the resolution reaction of the resist is a reaction that an acid produced by exposure decomposes a basic resin which is a main component of a resist material or changes molecular structure to make the basic resin soluble in a developing solution.
These objects and still other objects and advantages of the present invention will become apparent upon reading the following specification when taken in conjunction with the accompanying drawings.